# Request Validation Error Contract

> Use when changing backend request parsing, validation, error responses, exception mapping, or client-visible failure contracts.

- **Type:** Skill
- **Install:** `agentstack add skill-jukrap-ai-agent-playbook-request-validation-error-contract`
- **Verified:** Yes — security-reviewed for prompt injection and unsafe behavior
- **Seller:** [jukrap](https://agentstack.voostack.com/s/jukrap)
- **Installs:** 0
- **Category:** [Agent Skills](https://agentstack.voostack.com/c/agent-skills)
- **Latest version:** 0.1.0
- **License:** MIT
- **Upstream author:** [jukrap](https://github.com/jukrap)
- **Source:** https://github.com/jukrap/ai-agent-playbook/tree/main/skills/backend/request-validation-error-contract
- **Website:** https://www.npmjs.com/package/ai-agent-playbook

## Install

```sh
agentstack add skill-jukrap-ai-agent-playbook-request-validation-error-contract
```

Requires the [AgentStack CLI](https://agentstack.voostack.com/docs/cli). Works with Claude Code, Cursor, and any MCP-compatible agent.

## About

# Request Validation Error Contract

Protect request and failure contracts before changing backend validation or error handling.

## Workflow

1. Identify route, handler, schema, DTO, middleware, exception mapper, client callers, and documented error shape.
2. Separate parsing, validation, authorization, business rule failure, conflict, rate limit, and unexpected error paths.
3. Preserve stable status codes, error codes, field paths, localization keys, and retry semantics unless the change is explicitly versioned.
4. Keep sensitive values out of error bodies, logs, traces, and validation messages.
5. Verify success, invalid input, missing permission, conflict, not found, and unexpected failure paths.
6. Pair with `api-contract-boundary` when frontend mocks, generated clients, OpenAPI, or external consumers depend on the shape.

## Reference

Read `references/request-error-contract.md` before editing validators, DTOs, exception filters, middleware, or error response schemas.

## Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

- **Author:** [jukrap](https://github.com/jukrap)
- **Source:** [jukrap/ai-agent-playbook](https://github.com/jukrap/ai-agent-playbook)
- **License:** MIT
- **Homepage:** https://www.npmjs.com/package/ai-agent-playbook

Install and usage instructions live in the source repository linked above.

## Pricing

- **Free** — Free

## Security capabilities

Automated source analysis of v0.1.0 — what this tool can access:

- **Network access:** no
- **Filesystem access:** no
- **Shell / process execution:** no
- **Environment & secrets:** no
- **Dynamic code execution:** no

*"Yes" means the capability is present in the source — more access means more to trust, not that it is unsafe.*


## Versions

- **0.1.0** — security scan: passed — Imported from the upstream source.

## Links

- Listing page: https://agentstack.voostack.com/l/skill-jukrap-ai-agent-playbook-request-validation-error-contract
- Seller: https://agentstack.voostack.com/s/jukrap
- Browse the marketplace: https://agentstack.voostack.com/browse

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Listed on AgentStack — the marketplace for AI agent skills and MCP servers. Every listing is security-reviewed. Creators keep 70%.